Process of making ferrous products faced with stable surface alloys



July 7, 1 931.

P. A. E. ARMSTRONG PROCESS OF MAKING FERRUS PRODUCTS FAGED WITH STABLESURFACE ALLOYS Filed March 30. 1929 INVENTOR ATTORN EY Patented July 7,1931 UNITED STATES PATENT OFFICE m... i E. msm., .F ,.Ew m, N. i..RHSSUED rnocEss or mme Emmons PnoDUcTs EAoEn WITH STABLE SURFACE ALLoYsApplication med Harsh 30, 1929. Serial llo. 351,314.

My invention is of a process for making Vferrous products with weldedfaces of stable surface alloy material.

My present invention is a continuation in 6 part of my applicationSerial No. 63,975, filed October 21, 1925.

According to the present invention, ferrous metal is Welded to a thinsheet of stable surface alloyjby casting the ferrous metal against sucha thin sheet of stable surface alloy, and by thereafter subjecting theresultmg welded product to hot mechanical working, such as hot rolling,for example,

with the ferrous surfaces in .contact, a product is obtained with aninner portion of ferrous metal and outer surfaces of stable surfacealloy on its opposite sides.

In the accompanying drawings, I have illustrated a preferable mode ofcast-ing the ferrous material against and thereby welding it to a stableally material preparatory to the final step of hot mechanical working,as hot rolling, to produce the final product.

Fig. l is a plan view of an ingot mold with stable surface materialtherein, prior to casting.

Fig. 2 is a verticalsection of the ingot moldduring casting of the-ferrous metal; and

0- Fig. 3 is a section of the final rolled product.

In the showing selected for illustration, two thin sheets 10, 10 'ofstable surface material are placed back to back, with preferably a layerof asbestos 12 therebetween, and

same inserted in slots 14, 14, forming. sub

stantially central extensionsof the ingot cavity 16 in the ingot mold'18.

Molten ferrous metal 2() when poured into the ingot mold at one sideofthe partition so formed passes in part through the hole 22 formed inthe stable surface alloy sheets and the asbestos at preferablythe lowercentral portion thereof, so that a` part of the resulting ingot is toppoured and the'other part is bottom poured. Such shrinking of the castmaterial as takes place during'cooling tends to cause the ferrous metalto shrink upon and against the stable surface alloy sections arranged inthe interior of the mold,

and lto avoid any effect of shrinking awayv y therefrom.

The resulting ingotis separated into two parts on the parting planeproduced bythe asbestos layer, and when hot rolled, with the .sides 24,24 ofthe ferrous metal arranged m contact with one another and thestable surface alloy faces looking outwardly and adapted for coming incontact with the roll surface, the ferrous metal is welded into `.asubstantially homogeneous interior portion, producing the final productshown in Fig.v 3 and comprising the interior portion 26 of ferrousmetal, having outer opposite face or surface portions 28,28 of stablesurface alloy material.` The faces 24, 24; ofthe ferrous metal that areto' .be contacted may be machined smooth, or pickled before thecomposite element is subjected to hot rolling. This facilitates gettinga good weld. The

ingot parts may be separately rolled or otherwise hot Worked into billetor bar form if desired, before being assembled in pairs as described forthe` final hot rolling.

The ratio of the thickness of the cast backing materiall to thethickness of the stable surface facing welded thereto in casting is to aconsiderable extent dependent upon the thickness desired for thefinished rolled-down product. In general, this ratio is less for theproduction of very thin sheets than for the production of thickersheets, since withthe v former a larger proportion of the sheetthickness must be made up of the stable surface layers in order toprevent exposure of the backing in the course of working,l drawing,etc., for the production of articles, particularly cupped articles,therefrom, and in the ordinary uses and Wear to which the articles aresubjected. With thicker sheets relatively is materially under 3: 1, theweld is generally poor and unduly high temperatures have to be used forthe molten'metal, which may result in porous ingots, ingot cracks andheavy shrinkage. With the production of relatively thicker finishedproducts the ratio above referred to may be advantageously 5: 1 orhigher, and with such relation between the cast metal and the'solidmetal sheet 1nserted in the ingot mold, good welds can be producedwithout the use of unduly high heat for the molten material.

Various stable surface alloys may be used,

' as for example so-called rustless steel or iron with about 7-30% ofchromium and with various other alloying materials. The choice offerrous material to be cast against and welded to the sheets of stablesurfacing material will depend upon requirements, but for generalpurposes carbon steel of .05% to 1% of carbon gives good results.

The rolled metal faced `with welded surfaces of stable surface alloy canbe used for various products and articles of which a few are, forexample, sheets, rooings, conductor pipe conduits, shingles, cookingutensils, containers for foodstuffs, and articles for taking the placeof tinware, zincware and plated articles generally.

I claim: Y

1. Process of making sheets of ferrous metal faced on opposite surfaceswith stable surface alloy which consists in casting ferrous metalagainst solid stable surface alloy material in relatively thin sectionssuch that the thickness of the alloy is not more than onethird thethickness of the ferrous metal cast against it, and subjecting theresultingfwelded product to hot mechanical working in pairs with theferrous surfaces arranged in contact and the stable surfaces facesdirected outwardly.

2. Process of making sheets of ferrous metal faced on opposite surfaceswith welded surface portions of stable surface alloy, which comprisesarranging relatively thin sections of solid stable surface material backto back in an ingot mold, casting ferrous metal between the insert andthe mold walls, separating the resulting ingot parts, each comprising aferrous metal part and a stable surface alloy part welded thereto incasting, and reversing same to bring the ferrous surfaces into Contactand the stable surface alloy facing outwardly on opposite sides, andsubjecting to hot mechanical work, as by hot rolling, whereby theferrous metal part is welded into a homogeneous interior portion andsame is faced on its welded thin surface portions of stable surfacealloy material.

In testimony whereof, I have signed my name hereto,

PER-CY A. E. ARMSTRONG.

opposite sides with

